The present disclosure relates to document reading devices configured to convey an original document to a reading unit and read an image of the original document while conveying the original document and relates to image forming apparatuses.
Some document reading devices employ a method in which a pair of reading units are arranged one for each of two sides of an original document to allow parallel reading of both sides of the original document being conveyed. In most of these document reading devices, generally, a CIS (contact image sensor) is used as a reading unit for reading one side of an original document. On the other hand, a CCD (charge coupled device) is often used as a reading unit for reading the other side of the original document. Such a document reading device further includes: a white color reference member disposed facing the reading unit and used to acquire white color reference data; and a contact glass plate interposed between the reading unit and the white color reference member and used in conveying an original document. A document conveyance surface of the contact glass plate on which the original document is to be conveyed comes into contact with the original document to be read by the reading unit. The white color reference data acquired by the reading of the white color reference member by the reading unit is used for shading correction in an image forming apparatus equipped with the document reading device.